Hydronephrosis Hydroureter - Erler Zimmer

Hydronephrosis Hydroureter - Erler Zimmer

Clinical History

A 49-year-old man presents with a 6-week history of malaise, urinary frequency, and hematuria. Further inquiry revealed intermittent left flank pain. Abdominal ultrasound revealed severe hydronephrosis and hydroureter, secondary to multiple obstructing ureteric calculi at the uretero-vesical junction. He underwent a successful left nephrectomy and ureterectomy, resulting in a full recovery.

Pathology

This is the patient's left nephrectomy and ureterectomy specimen. The kidney has been bisected, and the cut surface of both halves is displayed, mounted in continuity with the ureter, which has been opened. The kidney is grossly hydronephrotic, with considerable atrophic thinning and loss of renal parenchymal tissue. The ureter is extremely dilated and contains small brown-black calculi with irregular sharp surface projections, identified as calcium oxalate stones.
This case illustrates hydronephrosis and hydroureter resulting from calculi obstructing the lower end of the ureter.

Further Information

Hydronephrosis, or obstructive uropathy, manifests as the dilation of the renal pelvis and calyces due to an obstruction in urine outflow, which can occur at any point in the urinary tract. Obstruction sources include congenital anomalies, urinary calculi, urinary tract tumors, inflammation, prostatic hypertrophy, and prostate tumors. Symptoms of hydronephrosis depend on the underlying pathology causing the obstruction (e.g., renal colic pain with calculi), the duration of obstruction (acute or chronic), the site (unilateral or bilateral), and its completeness.
If the obstruction persists, it ultimately results in increased pressure proximal to the site. Retrograde transmission of this pressure through the collecting ducts to the cortex causes progressive kidney atrophy with dilatation of the renal calyces and pelvis. The pressure also compresses medullary vasculature, leading to ischemic medullary damage. Glomerular filtration persists until late in the disease process, gradually diminishing or ceasing. Obstruction triggers an interstitial inflammatory process leading to fibrosis. Ultrasound is a key diagnostic tool, followed by CT or urogram. Most obstructing lesions necessitate surgical intervention to relieve the blockage. Surgical approaches vary based on the cause and may include nephrostomy or stenting for upper urinary tract obstruction and urinary or suprapubic catheter insertions for lower urinary tract obstructions.